Donald Trump and Ted Cruz are locked in a neck-and-neck race for the Republican nomination, and the strain is showing, with Mr. Trump resorting to name-calling and Mr. Cruz implying that his rival is a closet Democrat. (Associated Press) more >

Real estate mogul Donald Trump has built what is now a 20-point lead over his nearest 2016 GOP presidential rival in New Hampshire, with Sen. Ted Cruz of Texas moving into second place, according to a new poll.

Mr. Trump was at 34 percent in the CNN/WMUR survey released Wednesday, followed by Mr. Cruz at 14 percent and Sen. Marco Rubio of Florida and former Florida Gov. Jeb Bush at 10 percent apiece.

Sen. Rand Paul of Kentucky, New Jersey Gov. Chris Christie and Ohio Gov. John Kasich were in a three-way tie for fifth place at 6 percent apiece.

A CNN/WMUR survey released last month had Mr. Trump in first at 32 percent, followed by Mr. Rubio at 14 percent, Mr. Christie at 9 percent, Mr. Bush at 8 percent, Mr. Kasich at 7 percent and Mr. Cruz at 6 percent.

In the new poll, 30 percent of likely GOP primary voters also said they would not vote for Mr. Trump under any circumstances, followed by Mr. Bush at 18 percent and Mr. Christie at 9 percent on that question.

But by wide margins, voters chose Mr. Trump as the best candidate to handle both the economy and the Islamic State terrorist group. Thirty-four percent said foreign policy or national security is the most important issue in deciding who to vote for, followed by jobs or the economy at 26 percent.

On the question of which candidate has the personal characteristics and qualities a president should have, Mr. Trump and Mr. Cruz were tied at 16 percent apiece, with Mr. Rubio at 14 percent and Mr. Bush at 13 percent.